An exercising apparatus should allow the user to strengthen specific muscles used in the sport. For a swimming simulator, the rotation of the body and its positioning relative to the direction of forces exerted should simulate the motions involved in swimming in water. Existing exercise devices, include swim benches which allow some form of rotation of the body, however independent rotation of the upper and lower body portions of the user is not provided by the prior art systems with the exception of the pivotable torso exercise support in U.S. Pat. No. 5,628,632 issued to Doane on May 13, 1997.
Prior art swimming simulator systems require the user to lay horizontally on a bench surface and to pull against a resistance. When said resistance is high, the user's body has a tendency to slide forward on the bench. The user is forced to activate muscles not normally used in swimming in order to hold themselves in place and prevent the body from moving forward relative to the bench. Prior art systems that require the user to lay horizontally on a bench surface also result in a large space requirement for the devices as there must be room for the fully extended body with legs extended horizontally behind the device and hands outstretched in front of the head.
U.S. Pat. No. 4,674,740 issued to lams et al. on Jun. 23, 1987 discloses a swimming trainer which allows for a rocking motion of the body during execution of the stroke. The user's torso and hips in the lam device lay horizontally on a common bench and the entire frame moves as one, causing the entire body to rock. A drawback to this design is that the lower body must rotate with the upper body in the same direction and to the same degree.
Another related swimming machine uses two independent supports for the upper and lower body. In U.S. Pat. No. 5,158,513, issued to Reeves on Oct. 27, 1992, the user's body is supported in a generally horizontal position so the user can pull against hand paddles which activate a resistance mechanism. However, the support for the upper body which allows for chest rotation forces the chest out of line with the head because its center of rotation is below the body. A proper stroke technique requires that the body should rotate about a center axis which is approximately in line with the spine of the body.
U.S. Pat. No. 5,354,251, issued to Sleamaker, discloses a swimming machine that uses a bench support for the user's body where the bench tilts from side to side. U.S. Pat. No. 7,585,256, issued to Harbaugh IV et al., also allows the bench to pivot on an axis directly underneath the body support bench. Each of these allows for movement and rotation of the body from side to side in order for the user to lean into the stroke. However, this type of movement causes a user to weave from left to right while he/she progresses through the water. Thus, the swimmer would be traveling a greater distance because they would not be moving in a straight line.
U.S. Pat. No. 5,971,902, issued to Robertson et al., discloses a lumbar extension machine that supports the user in a manner very similar to the equilibrium position, or the resting position, of the present invention, however its support pad is fixed in one position and does not allow the user to freely rotate their torso.
Other exercising devices such as that of U.S. Pat. Nos. 4,830,363 and 3,791,646 are known, but the prior art does not provide for independent movement of the user's upper and lower body and where the torso or upper body portion is permitted to rotate with a center of rotation that is located above the bench and approximately in line with most users' spines. The prior art also does not allow the user to operate the device in a leaning position that saves horizontal space and prevents unwanted movement of the user's body relative to the device.